STEM/EELS Analysis of Conversion Reactions in Cycled FeOF/C
نویسندگان
چکیده
Transition metal fluoride/carbon nanocomposites have been under extensive investigation in the past ten years due to their theoretical high capacity in the range of 500 to 800 mAh/g [1]. In this study, the structural changes of FeOF/C positive electrode during lithiation/delithiation have been studied as a function of number of cycles (up to 20) under constant cycling current of 50 mA/g and at 60°C. ADF-STEM imaging technique combined with electron energy loss spectroscopy (EELS) and selected area electron diffraction (SAED) were used to track the phase evolution of FeOF/C and chemical composition with bonding characteristics of phases present after cycling.
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